Centralized clinical testing of diagnostics is expensive and time consuming, causing delays in health care delivery. Recently, there have been substantial efforts in both the development and the availability of rapid point-of-care diagnostic assays for use in both clinical and non-clinical settings that address a variety of diseases and medical conditions. This has led the Food and Drug Administration, as well as the World Health Organization, to set forth suggested requirements and define a simple point-of-care device as fulfilling the ASSURED criteria (affordable, sensitive (>43%), specific (98%), user-friendly, reproducible/rapid, equipment free, and deliverable to those in need with no operator analysis or intervention).
Human papillomavirus (HPV) infection is the most commonly-diagnosed sexually-transmitted disease in the United States. Persistent infection with high-risk HPV has been demonstrated to play a role in several cancers. Most significantly, it has been demonstrated that high-risk HPV causes most, if not all, cervical cancers (99.7%) as well as oropharyngeal head and neck squamous cell carcinoma (45-90%). In the case of cervical cancer, screening for precursors by cytology (Papanicolaou test) has been successful in countries with adequate resources. However, guidelines in the United States and Europe recommend HPV testing in addition to cytology in women over the age of 30 (WHO and CDC). Currently, testing for HPV consists of a DNA screen at a clinical diagnostic laboratory.
Thus, there is a need for a rapid, low-cost, highly sensitive and specific diagnostic assay for the detection of HPV that can be performed in a non-clinical setting. A prior method can be used to identify antibodies for the HPV16 E7 in invasive cervical cancer and head and neck cancer screenings. However, this assay requires a complicated biochemistry sequence that is not feasible in a low-cost point-of-care device.
Also, current point-of-care diagnostic assays lack the ability to provide quantitative diagnostic information. This limits the ability of clinicians to accurately diagnose patients and accurately monitor their disease progression or response to a particular therapy.
Therefore, low-cost point-of-care immunoassay systems and methods that provide quantitative diagnostic information are needed.